Just had my Skyview Dual ADAHRS done last week. Check the latest install manual. It advises to enter TEST MODE and i did. Both ADAHRS then display on the Primary EFIS. And both done at the same time. No turning on & off was required. That may have been old process, not sure. This was the 3rd test for my plane and at a different shop each time.
My advice - Do not leave the plane while this test is being done. On 2 occasions me being there prevented the tech from potentially going off on a tangent ($$$). They do a lot of different systems so i dont expect them to know the Dynon system without reference to docs and my info on my system. I also think key to the test is the initial setup. The tech had issues with driving the altitude to Neg 1,000’. Did i have a leak in the system? No, his suction cup on my static port didnt seal well. Took him a few tries. This year‘s test went to 20,000‘ no problems. Last test the tech could only get it to 16,000’. Did it miraculousy improve - doubt it. I think his equipment wasnt setup right. Not going to 16K so that was fine. Glad to know my system hasnt degraded and is good to 20,000’.